![Captain Underpants and the Revolting Revenge of the Radioactive Robo-Boxers (Book 10)](/userFiles/uploads/captain-underpants/captain-underpants-and-the-revolting-revenge-of-the-radioactive-robo-boxers-book-10/CUP_10_Color.jpg)
When we last saw our heroes, George and Harold, they had been turned into evil zombie nerds doomed to roam a devastated, postapocalyptic planet for all eternity.
But why, might you ask, didn't the amazing Captain Underpants save the boys from this frightening fate? Because Tippy Tinkletrousers and his time-traveling hijinks prevented George and Harold from creating Captain Underpants in the first place! Now, having changed the course of human history forever, they'll have to figure out a way to CHANGE IT BACK!